code for price tracking based on api

There are two main parts to the system

1. Transactor stores and logs the transformations to the database
2. Strategy, wraps your custom modules to interact with the transactor

lib/strategies/omega_pricing.ex impliments the contract of strategy for the omega api. You could extend your own by writing your own modueles and using Strategy

Strategies expose a make_request() function that will call the api and merge the changes into the database. By deriving from Strategy, The Transactor code can be resued verbatim.

You can call make_request at periodic intervals to gather data for the database. a library such as quantum-elixir would be perfect for this and could be mounted in a supervision tree.

I did make a few assumptions

1. http with get responses. I did add a case statement where a post handler could be added
2. The exposed method takes no option. This is to make it easier to mount it in a cron function.
3. we want to support multiple companies so I added a company code to the product model

I wasn't sure if phoenix was allowed so I built the test harness with support for ecto and mocking http requests for httpoison myself.

• ecto
• exvcr to mock http requests for testing
• timex for time handling

to run the tests, simply run

mix deps.get
mix test